A1: We have discussed this issue with local communities and NGOs members as part of our prototyping plan exercise: Many slums in Mumbai are very dense, already have permanent structures and several stories. Government policy is prioritizing the introduction of improved sanitation in these neighborhoods. We discussed the uses of OpenReblock with SPARC (local NGO) and with Mumbai City Ward Engineers. Both found it useful in analyzing the intricate spatial structure of slums and revealing where accesses could be introduced. They stressed that analyses are most useful in 3D, integrating the height of buildings and their structural quality. They also emphasized that the priority in terms of policy are shared toilet blocks. They suggested using OpenReblock to find shortest paths to existing sewer lines for strategic future planning. In Greater Cape Town, most slums are part of suburban townships. These are less dense and established than in Mumbai but present other problems: most households have their own shack and are less tightly interdependent socially. Most slum areas are prone to flooding as they stand on sandy low-lying ground so considerations of drainage are very important for neighborhood resilience.

By comparing and contrasting these two use cases we derived a number of design requirements for OpenReblock to be co-designed and tested by our users in local communities and NGOs (see attachment). We see the main challenge as being able to create design that makes the use of OpenReblock very easy and accessible for slum communities and NGOs to use. From the beginning a wide range of local actors, technical and organizational, within communities and SDI NGOs are involved in the process. As SDI does in all its other activities, two or three cities and countries start exploring a new process and gradually others visit them and pressure for refinement and adaptation to serve their own processes. The work of OpenReblock is the next stage of a process, following on the heels of our recent work creating a base data gathering system and digitalizing that data over maps.

A2: The reblocking process already exists and is well exercised as a practice in community organization. Both SPARC (SDI’s Indian Federation) and CORC (SDI’s South African Federation) have performed reblocking processes a large number of times. The OpenReblock project builds on these existing processes. Our digital and physical tools complement and facilitate this personal and interactive process, which can otherwise be very slow, laborious and contentious as hard trade-offs are involved. The planned uses of technology and data fit in strategic places of this process where uncertainty, technical difficulty or coordination become crucial to create a common view and an evolvable practical plan.

We already have open-source data collection and mapping tools that can be used in offline environments. These are already used by SDI Federations and thus are a seamless part of OpenReblock. Once the mapping and data collection is done, the users connect to the internet to upload the data so that we can run the reblocking algorithm that suggests optimal access configurations (this is, at the moment, too processor-intensive to do offline). Users will then be able to download and print out the resulting maps for offline use, so they can share them with the community for discussion. Thus, we believe that we have a robust and well-integrated work flow for the idea and that additional elements can be added in modular ways.

A3: The primary benefit of OpenReblock is to the local slum community. All SDI efforts are community-led and prioritize the needs of the community ahead of other objectives. The process simply does not work if people do not feel they will derive sufficient benefits for themselves: They will walk away. The reality is that while lots of data is now being collected, it is always a challenge for it to be utilized in the context of slums. Creating visual digital images for a dialogue within the City and between communities is not a process in place and so communities generating this data, getting internal agreements within their members and presenting it to cities is an area of focus of great value to SDI affiliates. It’s a digitalized visual manifestation of what they do presently.

While these advantages accrue to slum communities, it is also important to realize that a virtuous cycle of resilient development is created by the reblocking process that benefits local governments and other people in the city. By facilitating the introduction of services in the home and regularizing land tenure, Cities relieve the burden of maintaining public services that often break down from intense use and that do not generate revenue. Billing of services to households and businesses provides a sustainable economic model for their expansion and real estate taxes allow the City to improve, but also forces it to become more accountable.